nineteenth century and the early part of the twentieth century was a time of hardship for many Americans, and a time of extreme injustice for several groups, as well. African-Americans were strictly segregated and subjected to institutional racism by the state and local governments in the South and by cultural sentiments, and Native Americans continued to be pushed into ever-smaller reservations and subjected to a host of other injustices, as well. The former group was being ostracized from mainstream American society, while the latter group was forced to assimilate or to live in squalor, and leadership in both groups was split, as well. Meanwhile, expansion into areas of the continent that had been unsettled increased due to mining efforts and for other reasons, as well, though by the early twentieth century the frontier had largely been closed and the first phase of America's history, at least according to some observers, had come to a close.
After the Civil War, a second industrial revolution occurred marked by the growth in transportation (primarily railroad) and communications (telegraph and telephone) technologies. As business expanded and production and distribution methods grew more efficient, certain entrepreneurs were able to become incredibly wealthy by coordinating and controlling the elements of their business, and the age of the mega-wealthy industrialists was born. In response to this and in reaction to other changes wrought by the increasing industrialization of the country and indeed the world, labor unions began to grow in numbers and in strength, in order to combat rising disparities in wealth between the classes and the poor working conditions that most people had to endure. The majority of the working population was unskilled an uneducated, and prospects for changing this situation were rather slim -- workdays were long and many children had to labor as well, while families rented housing and purchased the means of subsistence often from the same bosses that controlled their wages. All in all, this growing industrialization was great for a select few and laid the foundations for later national prosperity, but was the source of many problems for standard workers.
The same period of increasing industrialization saw an increase in urbanization and the first emergence of suburbs, as transportation allowed the middle class to leave the city while new technologies and a strong labor force allowed cities to build upward and outward. High levels of immigration also had an impact on the culture of cities and the era, with ethnic enclaves in major urban areas growing and with the demographics of the country shifting heavily towards immigrants rather than those born on American soil. All of this activity led to new opportunities for entertainment, including the Vaudeville circuit and large city parks, while at the same time the concept of social Darwinism was creating a sense of competition and a hands-off attitude towards many of the social problems that were emerging. This all had an influence on literature as well, ushering in the era of realism in American Literature with such authors as Mark Twain and many others commenting on conflicts and disparities seen in nature, in the social order of things, and within Man himself.
The Gilded Age at the end of the nineteenth century was a period of several key issues in politics, from the running of political "machines" in major cities by the two loyally-supported political parties to the emergence of other parties that attempted to effect more radical change. The Populist party was one of these; formed initially as a party that joined various Farmers' Alliances and their interests together, the Populist Party had a platform of greater government regulation, greater rights for farmers and laborers, and more direct attention to and action towards certain social issues. This party was ultimately unsuccessful and ended up being essentially subsumed into the Democratic party, but though it did not meet with direct success it did help to set the agenda and to spur the two larger parties -- both of which had grown rather complacent and reluctant to rock the boat -- to greater levels of meaningful action. Reforms would continue for decades, but their seeds were sown most definitely in the Gilded Age in response to the needs of those with less gilded lives.
Social Darwinism continued to be a major influence for decades after Darwin's theory of evolution was published, and U.S. businesses and the government used the concept to justify expansion into under-developed countries in what was dubbed a "new Imperialism," focused more explicitly on economic exploitation than political or cultural control. Missionaries had similar thought processes, and tried to spread the word of Christianity to the "heathens" in other countries that had not heard of the Bible or the religion, and in this way indigenous cultures did end up under attack during this period. War with Spain in 1898 added new territories to the United States' direct or effective control, and President Theodore Roosevelt expanded America's empire and the control that could be exercised over its "colonies" by increasing the nation's military and particularly naval power, cementing the dominance of the United States on world affairs for some time to come.
New wealth abroad meant new opportunities for change at home, and while America's influence abroad might not be seen as progressive its domestic policies certainly were. President Theodore Roosevelt worked to regulate business and to promote workers' rights, and responded favorably (though not as favorably as some perhaps thought he should) when it came to a variety of social issues raised by middle-class concerns and by publications and journalists dubbed "muckrakers," which called attention to things like atrocities in the meat packing industry and problems with drug safety. President William Howard Taft tried to keep up the same trust-busting, but business interests in the Republican party proved to be too strong and the reform efforts were not as successful as many in the party desired. Theodore Roosevelt ended up the nominee for the hastily formed Progressive Party after failing to receive the Republican nomination in an attempt to oust Taft from the Presidency, and the split of the Republican vote in 1912 allowed Democrat Woodrow Wilson to win the election; though still progressive, there were key differences in Wilson's approach to social issues and the rights of the country's lower classes.
Wilson's presidency was marked by conflicts, including with Mexico after the United States' southern neighbor underwent several military coups and, of course, World War I. The First World War was caused by the tense division of Europe that existed during the early part of the twentieth century, and was ultimately sparked by the assassination of Archduke Ferdinand, heir to the Austro-Hungarian Empire. Ostensibly neutral at first, business interests and the growing scale of the war -- especially Germany's attempt to persuade Mexico to wage war on the United States -- eventually drove the U.S. into the fray. Wilson concocted a peace plan that was utilized to end the large empires in Europe and bring about more democratic nations, but the U.S. never ratified the treaty and the addition of a "war guilt" clause affecting Germany laid the foundation for the rise of Hitler and the Nazis.
The decade after World War I was a time of cultural expansion and retraction; jazz, the Harlem Renaissance, and more open sexuality were all representative of growing freedoms, but anti-immigrant sentiments and fears of Communism also rose during this period. Reactions against social and cultural changes grew more extreme, and art and literature grew more bleak in the style known as Modernism. This was also the period in which official policy experienced a "return to normalcy" and a cessation of the progressive changes that had been made. The economy initially boomed under a more lax government, but this would spell disaster with the Great Depression.
The first thing President Franklin Delano Roosevelt did when he took office was to try to stabilize the United States' economy, which was in tatters in all sectors. The first round of New Deal programs achieved some stabilization through essentially short-term efforts, while the Second New Deal was aimed at achieving more lasting change and stability in the economy through more extensive and foundational efforts. The power of the federal government also grew in this period, and regulation of business efforts was to increase extensively as well in an effort to maintain stability and a modicum of prosperity for all. This led to no small amount of backlash from critics, who saw many of these new practices as socialist and counter to the principles of individual liberty and property rights, all while culture became both increasingly honest and escapist as evidenced by various emerging media.
During its time of internal rebuilding and stabilization, the United States became much more isolationist in its foreign policy, trying to let the rest of the world deal with its own problems. Those problems mounted instead, however,…